What advantage does pristiq desvenlafaxine have over Effexor venlafaxine?

Answer 1

None. Quoting from Dr. Carlat Psychiatry Blog: 1. It's a blatant patent extender. Effexor XR, which brought in $3.8 billion for Wyeth in 2007, is losing patent protection this year, and Wyeth is introducing desvenlafaxine, which is simply Effexor's main metabolite, as a "novel antidepressant." There's nothing novel about it. Every patient who takes Effexor produces Pristiq in their own body, at no additional charge.

2. It's not very effective. In the studies released so far, Pristiq just barely squeaks by placebo on the Hamilton Depression scale. In the U.S. study, Pristiq decreased the HamD by only 2 points (-11.5 vs. -9.5 for placebo), and in the European study, the differences was 2.5 points. And for the higher 100 mg dose, there was no difference between drug and placebo for U.S. patients.

3. It is not more easily dosed than Effexor XR. The main Wyeth marketing point for Pristiq is that patients can get better by taking the beginning dose of 50 mg, eliminating the need for a complicated upward dose titration process. Sorry, but this is not different from Effexor. If you look at one of the original fixed-dose studies of Effexor, comparing patients taking 75 mg, 225 mg, or 375 mg, you'll find that the 75 mg dose separated from placebo as well as Pristiq's 50 mg. Psychiatrists typically begin Effexor at either 37.5 or 75 mg/day. At least with Effexor XR, when you keep increasing the dose, efficacy improves, meaning it actually has an efficacy advantage over Pristiq, because when you increase the dose of Pristiq, you lose efficacy, according to the U.S. study data.

4. It has no meaningful metabolic advantages. Wyeth will highlight the fact that Pristiq is not metabolized by the P-450 system and therefore does not have any drug-drug interactions. Well, guess what, Effexor has no clinically meaningful drug-drug interactions either.

5. Wyeth's own lead investigator is unimpressed. I spoke briefly with Dr. Michael Liebowitz, the Columbia University psychiatrist who led the major Pristiq trials. Pristiq, he said, "is another SNRI--it is not a revolutionary drug." It may be more tolerable at the starting 50 mg dose, he said, but only time will tell if it truly is clinically useful. "If it is useful, then it will make money for the company, and if it is not, it won't." POSTED BY DANIEL CARLAT, M.D. AT 8:31 AM LABELS: PATENT EXTENDERS, PRISTIQ, WYETH PHARMACEUTICALS

**Different Answer - from someone who has actually used both meds!!**

I was on Effexor for sometime between 6 months and a year (it's been awhile so I don't remember the exact time period), and while it did help with my depression (it helped lift my mood), it made me extremely sleepy. As someone who is usually sleepy (due to my depression, so the docs tell me), something causing me to be even sleepier than usual was definitely bad :( Spoke with my doc and he said in order to counteract this I should take Effexor in the evenings (about dinnertime, not bedtime or I would still be sleepy in the morning). I take my other meds in the morning with breakfast, so it was hard for me to remember to take Effexor separately, by itself, in the evenings. For this reason, when Pristiq came out my doc switched me to that because he said that because it apparently skips a metabolic step (as compared to Effexor), it would not make me sleepy and I could take it with my other meds in the mornings. Yay!! So I am happy to report that, after switching to Pristiq, I did not experience a decrease in effectiveness as compared to Effexor in treating my depression, and I did not feel sleepy after taking the med. My insurance doesn't cover prescriptions, so for me Pristiq is way more expensive than Effexor, but luckily I was able to qualify for free medication through Pristiq's patient assistance program. So, from my point of view at least, there is a significant difference between Effexor and Pristiq, and if your doctor recommends Pristiq over Effexor, it's probably for a reason. You should try it out for yourself before deciding if it's worth any extra cost.